[SOLVED] Question about VLC m4a files.
Posted: 16 Apr 2011 20:06
Hi
I'm using VLC 1.2.0-git Twoflower (revision 5637ca8) and Ubuntu Karmic Koala 9.10.
I recently had a problem with FFmpeg.
When I created m4a files, they would not play in my 2nd generation iPod Shuffle Model A1204.
I asked about it on the ffmpeg-users mailing list.
It seems that the MPEG-4 "esds" atom is permitted to be expressed in either one byte or 4 bytes.
But this Shuffle can only play m4a files when the 4 byte method is used.
Previously FFmpeg saved the atom in one byte.
Now, FFmpeg's been changed to the 4 byte method.
So the files play OK in my Shuffle.
This is the relevant FFmpeg commit:- http://git.videolan.org/?p=ffmpeg.git;a ... 7c238e96b2
I've also tried converting files to m4a using VLC.
These files won't play on the Shuffle.
Is this because VLC uses the one byte method when creating m4a files?
I've uploaded some test files here:- http://www.mediafire.com/?inj58ld4n819eqj
test1.m4a is created using FFmpeg with this command:-
test2.m4a is created using VLC with this command:-
I'm using VLC 1.2.0-git Twoflower (revision 5637ca8) and Ubuntu Karmic Koala 9.10.
I recently had a problem with FFmpeg.
When I created m4a files, they would not play in my 2nd generation iPod Shuffle Model A1204.
I asked about it on the ffmpeg-users mailing list.
It seems that the MPEG-4 "esds" atom is permitted to be expressed in either one byte or 4 bytes.
But this Shuffle can only play m4a files when the 4 byte method is used.
Previously FFmpeg saved the atom in one byte.
Now, FFmpeg's been changed to the 4 byte method.
So the files play OK in my Shuffle.
This is the relevant FFmpeg commit:- http://git.videolan.org/?p=ffmpeg.git;a ... 7c238e96b2
I've also tried converting files to m4a using VLC.
These files won't play on the Shuffle.
Is this because VLC uses the one byte method when creating m4a files?
I've uploaded some test files here:- http://www.mediafire.com/?inj58ld4n819eqj
test1.m4a is created using FFmpeg with this command:-
Code: Select all
ffmpeg -i foo -acodec libfaac -ab 64k test1.m4a
Code: Select all
cvlc foo :sout='#transcode{acodec=mp4a,ab=64}:std{access=file, mux=mp4,dst=test2.m4a}' vlc://quit